Treatment of filamentary materials



Aug. 2, 1960 c. M. MOELTER 2,947,595

TREATMENT OF FILAMENTARY MATERIALS Filed Jan. 24, 1955 IN V EN TOR. 692-602) /7 Nofl n1? BY W ATfOP/VEYS United States Patent 2,947,595 TREATMENT OF FILAMENTARY MATERIALS Gregory M. Moelter, Bernardsville, N.'J., assignor to Celanese Corporation of America, New York, N.Y., a corporation of Delaware Filed Jan. 2-4, 1955, Ser. No. 483,601

16 Claims. (Cl. 8-1'51.2)

This invention relates to the treatment of filamentary materials and relates more particularly to the continuous treatment of filamentary materials with liquids.

It is common in the art to treat filamentary materials with liquids in a continuous manner. For example, one treatment of this type which has come into wide use involves the continuous desulfurizing, washing and bleaching, without intermediate winding operations, of freshly spun continuous filaments of viscose rayon. For such continuous treatments, machines known as threadstorage thread-advancing devices are employed. Generally, these are driven reel-like structures around which the filamentary material is caused to pass continuously in a helical path while it is subjected to the treatment with the liquid or liquids. Such devices are notentirely satisfactory since they are usually bulky, expensive, complicated, diflicult to string up, and prone to' cause breaks in the filaments, resulting in entanglement of the filaments and in shutdown of the devices.

It is therefore one object of this invention to provide a novel process for the continuous treatment of filamentary materials with liquids, and a novel thread-storage, thread-advancing device for carrying out such treatment, which will be free from the foregoing and other difii culties.

Another object of this invention is the provision of a new and improved method and apparatus for the continuous liquid treatment of filamentary materials in an efiicient and economical manner.

Other objects of this invention will be apparent from the following detailed description and claims.

In accordance with one aspect of this invention the filamentary material to be treated is introduced into a bath of treating liquid continuously in the form of a series of closed, or crunodal, loops arranged in a spiral whose diameter is greater than the diameter of said loops. Successive convolutions of this spiral rest on one another so that an annular mass of the filamentary material is built up in the treating bath. The treated filamentary material is withdrawn continuously, in uncoiled form, from the bottom of this mass of filamentary material;

- 'In oneconvenient form of apparatus for carrying out this invention, the filamentary material and the treating liquid are fed continuously to a tunnel to form a stream which falls freely from the funnel to the bath of treat irigliquid. The lower end'of the funnel is moved continuously in a substantially circular path about a vertical axis so that a spiralmotion is imparted to the falling stream of liquid and yarn. The bath oft'reating liquid is contained in a U-tube having an entrance arm and an exit arm. The entrance armtof the U-tube is constricted 'at'a pointbelow the surface of the bath. This constric- "ice It is desirable that the diameter of the spiral of yarn be somewhat smaller than the internal diameter of the entrance arm of the U-tube. For example, for a U-tube of 1% inch internal diameter, a suitable spiral has a diameter of about inch. This permits the coils of the spiral to move downwardly freely in the treating liquid but prevents the spiral from toppling over and becoming entangled. r

While best results have thus far been attained by the use of a U-tube it will be understood .that other'means for containing the bath of treating liquid and for supporting the spiral mass of filamentary material may be employed. For example, a straight tube constricted at,

its lower end may be supported in a relatively large tank filled with treating liquid and the filamentary material.

may be spiralled into thisstraight tube and withdrawn under some tensionfrom the bottom of the tube and through the tank. Such a tube may be perforated. or slotted, if desired. In fact, the straight tube'may be replaced entirely by suitable spaced guide members, for example, by parallel circularly disposed guide bars converging at their lower ends, which guide bars serve to keep the spiral mass of filamentary material in place. Also,

although it is most advantageous that the filamentary material be formed into a generally circular spiral and the treatment tube be of generally circular cross-section, shapes other than circular, e.g. elliptical or oval, may be employed, if desired. It is' preferred that the spiral mass of filamentary material be disposed substantially vertically during the process. However, if desired, the tubes or guide members may be so arranged that this spiral mass is disposed at an angle to the vertical, e.g. an angle of 30 to the vertical. t

It is generally advantageous to combine the filamentary material with a stream of liquid before the filamentary material enters the treating bath. The liquid stream adds Weight to the yarn so that it feeds morefreely into the bath. However, if desired, the yarn may be introduced into the treating bath without first coming into contact with the liquid, or the yarn may be merely moistened with the liquid before it enters the treating bath. The liquid may then be fed to the treating bath at some other point. Thus, a stream of treating liquid may be introduced into the exit arm of the 'U-tube and the liquid may be removed continuously from the entrance arm, so that the liquid and yarn move in opposite directions and there is a count-ercurrent treatment of the yarn.

If desired, a moving, rather than a stationary, treating bath may be employed while the yarn falls into the moving bath from a stationary, rather than a moving point. Thus, the U-tube holding the treating bath maybe moved as a unit about a vertical axis, tag. in a circular path about an axis parallel to the path of the falling yarn, or the U-tube may be pivoted at the bottom and the top of the U-tube, and the surface of the bath, moved in a closed tive liquids or washing liquids. i

The process of this invention maybe carried out using any desired filamentary material and any desiredtreating liquids. For example, it may be employed for the succ'essive acetylation and washing of incompletely acetylated cellulose acetate yarns; for the desulfurizing and washing of freshly coagulated regenerated cellulose yarns made from viscose, or for the saponification of cellulose acetate filaments. The filamentary material may be in the form of yarn of high or low denier 'or it may be in the form of a tow of, for .example, l0.0,000 or. 200,000,.denier;con-

' taining *many thousandsof individual filaments,-a. if :de:

sired However, this invention-shows its greatest practical benefittoryarnsof less than about 25,000denier rather than heavy tows, since the ordinary handling and treating of such tows does notpresentas. great a problem of tangling as thehandling and treatment of yarns.

By the use of the process and apparatus of thisinven- I tion the-filamentary material-isitreated efiiciently and fec onomically in acontinuousmanner .without developing tarigles,-snarls, slubsoribroken filaments 7 Y Theaccompanying drawing illustrates one form of the V apparatus of this invention wherein,

'Fig'jl is a diagrammatic .side view of theapparatus of this invention with partslthereof in .cross section,

FigvZ is an enlarged cross sectional side view of a portion of the apparatus shown in Fig. 1,..and

*Fig. 3'- is aflplan ,view, .taken along the line 3-3 of V Fig. 2, showing the general appearance of .the upper consuitablesourceof supply, notshown, by a pair of driven feed rolls '12intothe largeconical portion 13 of a funnel 14. A'treatingliquid from a supply. hereinafter referred to is fed to the funnel 14 through a .pipe 16 having a valve-17. The yarn 11 and the liquid leave the funnel 14 together through the stem 18..

The apparatus is constructed andarr'anged to impart a spiral -motion'to the stream'of liquid. and yarn leaving the lower end of the. stem'18 of the funnel 14. To this end the f unnel 14 is loosely supported by, and passes through, an apertured plate..19, with the upper edge of the aperture 21in said plateengagingthe conical portion 13 of-thefunnel near the point where said conical portion joins the stem 1-8; The aperture 21 is of larger diameter than the stem .18. Any suitable mechanical device, such as thearrangement of the motor 22 and slidably mounted eccentric member 23 illustrated. diagrammatically in'drawing Fig. 1, serves to movethebottom portion of the stem 18 in a substantially circular path about a vertical axis, such circular motion being permitted by the loose connection between the funnel 14 and the apertured plate 19. The spiralling stream. of treating liquid and yarn falls freelyfrom the funnel into arm 24, hereinafter referred was the entrance arm, of a U-tube 26 partly filled with said treating liquid,.which is maintained at the desired predetermined level by means of a flexible and adjustable overflow device 27, of conventional construction, attached to the second arm 28, hereinafter referred to as the exit arm, of said-'U-tube. .As the yarn passes into the liquid in the entrance arm 24,.it takes the form ofa series of small closed, 'orcrunodal, loops arranged in a spiral whose diameter is greater than the diameter of said loops. As shown in Fig. 3, each coil of this spiral of yarn 11 has the general appearance of a prolate epitrochoid, which is the curvedescribed by a point on the prolongation of the radius of a circle as said circle rolls along the outside of a fixed circle.

The entrance arm 24 of the U-tube 26.is constricted at apoint spaced below the level of the liquid therein, as by a plurality of circumferentially spaced hemispherical portions '29 projecting into the interior of said arm. The

yarn, being of higher density than the liquid, settles in spiral of yarn restingon thepreceding coil, toform a. generally cylindrical annular mass 31. When this mass of yarn has built up to'the desired level, which is generally the same as the level of the liquid in the arm or slightly higher, e.g. /2 inch higher, the lowest portion of the yarn 11 is withdrawn continuously past the inwardly projecting portions 29 and out of the exit arm 28, around a stripping guide 32, which serves to remove liquid from the yarn, through a traversing guide 33 of the usual type, and onto a driven rotating bobbin 34 or other suitable support where it is wound in the form of a package. The rate at which the yarn is withdrawn by the action of the bobbin 34 is so related to the rate at which the yarn is fed by the rolls '12 that substantially steady-state conditions are maintained in the U-tube 26. That is, if the treatment is such that the yarn does not change in length during the treatment, the linear rate of withdrawal is substantially equal to the rate of feed, while if the yarn increases or decreases in length during the treatment the linear rate of withdrawal is proportionately higher or lower, respectively, than the rate of feed.

It will be understood of course that in starting the treating operation it will be convenient first to pass the yarn through the entire U-tube 26, then to feed the yarn into the entrance arm 24without withdrawing any yarn from the U-tube and then, when the mass 31 of yarn in the entrance arm 24'has built up to the desired level, to begin the withdrawal of the yarn from the exit arm 28.f

Under some conditions there is a tendency for the mass 31 of yarn supported above the inwardly projecting portions 29 to become packed against the inner walls of the entrance arm 24 of theU-tube and to impede the free movement of treating liquid around the outside of said mass of yarn. To overcome this tendency the entrance arm 24 is so constructed as to provide one or more passageways or channels for such free flowof liquid. As shown in Fig. 3 the interior of the entrance arm 24 is fluted for this purpose. 7 r V In order to maintain the treating liquid at the desired predetermined temperature the U-tuhe 26 may be insulated or fitted with a heating or cooling jacket 36.

. The treating liquid overflowing from the U-tuoe 26 is led from-the overflow device 27, past a valve 39110 a storage, reservoir 41 from which it is Withdrawn and recirculated to the feed pipe 16 by means of a pump 42. If desired, the reservoir 41 may be by-passed and the liquid recycled directly through a pipe 43 and valve 44 to the feed pipe 16.

It will be understood that the time of treatment, i e. the residence time of the filamentary material in the treating liquid, may be regulated by appropriate changes in 'the amount of material in the spiral mass 31. This may be done, for example, by temporarily speeding up or slowing down the rate of withdrawal of the filamentary material or the rate of feed of such material until the spiral mass 31.is of the desired size and then resuming the original rates of withdrawal or feed. The time of treatment may also be changed by raising or lowering the level of the treating liquid in the U-tube by suitable adjustment of the overflow device 27. In addition, the time of treatment may be regulated, While keeping-the size of the spiral mass 31 constant, by appropriate changes in both the feed rate and the withdrawal rate. Combinations of all these methods may be employed, if desired. The following example is given to illustrate this inven tion further. All proportions are by weight unless otherwise indicated; I 4 I 7 Example posed of. 1350 filaments of stretched, oriented cellulose acetate having an acetyl value of 54.3%, calculated as combined acetic acid. The yarnis fed ata constant speed .of meters per, minute into the; funnel, whose upper conical Portion ta e d at. 2 1 1. 951 01. TPQ PQE- angle) and whose stem is 2 inches in length and inch nel is rotated, about a vertical axis, at a rate of 60 r.p.m." in a circle /2 inch in diameter. The yarn and acetylation mixture fall freely from the stem to the entrance arm of the U-tube, which U-tube has an internal diameterof 1% inches and an overall height of 35 inches. .iIhe

arms of the U-tube are vertical and of equal height, their center lines are spaced 5% inches apart andthe exit of the U-tube is provided with a device for maintain-.9 ing the level therein inches from the tops of said arms;

The inwardly projecting portions of the entrance arm have radii of inch and are situated inches from the top of the entrance arm, which is itself 13 inches below the bottom of the funnel. The yarn plaits into entrance arm in the form of a series of crunodal loops about inch in diameter, substantially symmetrically arranged about the center of the entrance arm, to form an annular pattern about inches in diameter. When this annular pattern has been built up to the level of the treating liquid in the U-tube, i.e. to a height of 10 inches above the inwardly projecting portions in the entrance arm, the yarn is withdrawn from the exit arm of the U- tube at such a rate that steady state conditions are maintained. Under these conditions the residence time of the yarn in the tube is 3 minutes and the yarn leaving the tube has an acetylxvalue of over 61%. The'apparatiis operates continuously for long periods of time without developing tangles, snarls, slubs or broken filaments in the yarn.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of my invention. 7

Having described my invention what I desire to secure by Letters Patent is:

1. In the process for the liquid treatment of filamentary material, the individual filaments of which all extend substantially in the direction of the length of said filamentary material, the improvement which comprises introducing said filamentary material into a liquid treating bath continuously in the form of a series of crunodal loops of said filamentary material arranged in a spiral having a diameter greater than the diameter of said loops, supporting said spiral in said bath with successive convolutions of said spiral resting on one another, and continuously withdrawing said filamentary material from the bottom of said spiral.

2. In the process for the liquid treatment of filamen tary material, the individual filaments of which all extend substantially in the direction of the length of said filamentary material, the improvement which comprises introducing said filamentary material into a liquid treating bath continuously in the form of a series of crunodal loops of said filamentary material arranged in a spiral having a diameter greater than the diameter of said loops, the density of said liquid bath being less than the density of said filamentary material whereby said spiral of yarn loops sinks in said bath, supporting said spiral in said bath with successive convolutions of said spiral resting on one another, and continuously withdrawing said filamentary material from the bottom of said spiral.

3. In a process for the liquid treatment of filamentary material, the individual filaments of which all extend substantially in the direction of the length of said filamentary material, the improvement which comprises introducing said filamentary material into a liquid treating bath continuously in the form of a series of crunodal loops of said filamentary material arranged in a substantially vertical, annular spiral having a diameter greater than the diameter of said loops, supporting said spiral in said bath with successive convolutions of said spiral resting U-tube in the form of a substantially vertical annular bottom of said spiral in unlooped condition through said stantially in the direction of the length of said filamentary material, the improvement which comprises continuously introducing a treating liquid and said filamentary material into a liquid treating bath, contained in a U-tube, continuously in the form of a series of crunodal loops of said filamentary material arranged in one arm of said spiral having a diameter greater than the diameter of said loops, said spiral being supported in said arm with successive convolutions of said spiral resting on one another, and continuously withdrawing the yarn from the U-tube.

5. Process for the liquid treatment of filamentary material the individual filaments of which all' extend substantially in the direction of the length of said filamentary material, which comprises continuously feeding said fila mentary material, feeding a liquid for treating the same into contact with said filamentary material to form a continuous stream containing said liquid and filamentary material, passing said stream downward in free condition from a point while rotating said point about a horizontal axis, introducing said stream into a bath of said liquid, said liquid being of lower density than said filamentary material, said filamentary material introduced into saidbathforming a series of crunodal loops arranged in a spiral having a diameter greater than the diameter of said loops, supporting and maintaining said spiral with successive convolutions of said spiral resting on one another, and continuously withdrawing said yarn from the bottom of said spiral in unlooped condition.

6. Apparatus for the liquid treatment of filamentary material, which comprises means for supplying a filamentary material the individual filaments of which all extend substantially in the direction of the length of said filamentary material, means for providing a bath of treating liquid, means for continuously introducing said filamentary material ,into said bath in the form of a series of crunodal loops arranged in a spiral having a diameter greater than the diameter of said loops, mean for supporting said spiral in said bath with successive convolutions of said spiral resting on one another, and means for continuously withdrawing said filamentary material from the base of said spiral in'utncoiled condition, said introducing means comprising means for bringing together said filamentary material and said treating liquid to form a continuous stream and for introducing said stream from a point into said treating bath, and means for moving said point in a closed path about a substantially vertical axis to impart a spiral motion to said stream.

7. Apparatus for the liquid treatment of filamentary material, which comprises means for supplying a filamentary material the individual filaments of which all extend substantially in the direction of the length of said filamentary material, means for providing a bath of treating liquid and means for continuously introducing said filamentary material into said bath in the form of a series of crunodal loops arranged in a spiral having a diameter greater than the diameter of said loops, said introducing means comprising means for bringing together said filamentary material and said treating liquid to form a continuous stream and for introducing said stream from a point into said treating bath, and means for moving said point in a closed path about a substantially vertical axis to impart a spiral motion to said stream.

8. Apparatus for the liquid treatment of filamentary material, which comprises means for supplying a filamentary material the individual filaments of which all extend substantially in the direction of the length of said filamentary material, means for providing a bath of treating liquid and means for continuously introducing said filamentary material into said bath in the form of a series means comprising a tube spaced above said bath, means forcontinuously ieeding said filamentary material and saidtreating liquid to said tube to form a stream which falls to saidbath, and means for moving the bottom portion of said. tubein a closed path about a substantially vertical axis to impart a spiral motion to said falling am i I 9. Apparatus for the treatment of filamentary material, which comprises means for supplying a filamentary material the individual filaments of which all extend substantially in the direction of the length of said filamentary material, a U-tube adapted to be filled at least partly with a treating liquid, means for continuously introducing said filamentary material into said treating liquid in onearm of said U -tube in the form of a series of crunodal loops arranged in a spiral having a diameter greater than the diameter of said loops, means for sup porting said spiral-With successive coils of said spiral resting on one anothen'and means for continuously withdrawing said filamentary material from the bottom of said spiral through said U-tube in uncoiled condition, said introducing means comprising means for bringing to gether said filamentary material and said treating liquid to ,form a continuous stream and for introducing said stream from a point into said arm, and means for moving said point in a closed path about a substantially vertical vertical axis to impart a spiral motion to said stream. 10. Apparatus as set forth in claim 9, said supporting means comprising a constriction in said U-tnbe.

11. Apparatus as set forth in claim 9, said introducing means comprising a funnel, means for continuously feed ing said filamentary material and said treating liquid to' said. tunnel to form a stream which falls to said treating liquid in saidarm and means for moving the bottom portion of said funnel substantially in the path of a circle, whose diameter is less than the diameter of said arm, about a substantially vertical axis to impart a spiral motion to said falling stream.

12. Apparatus as set forth in claim 11, said supporting means comprising projections extending inwardly from the walls of saidarm of said U-tube, said walls being fluted to provide channels for the free movement of said liquid around said spiral, said withdrawing means being constructed and arranged to withdraw said filamentary material through the other arm of said U-tube, saidapparatus also including overflow means for continuously removing said t-reating liquid fromsaid other arm and for maintaining said liquid at a predetermined constant level in said U-tube.

Zara-sea 13". 7 Apparatus for the liquid treatment of filamentary material, which comprises means for supplying a filamen tary material'the individual filaments of which all eigt'end liquid, means for continuously introducing said" filamentar'y material intols'aid bath in: the form of a series of crunodal loops of said filamentary material arranged a spiral having a diameter greater than the diameter'of" said loops, means for providing a passagewayfor. the

movement of said filamentary' material in said bath and. for supporting said spiral in said bath with successive:

convolutions vof'said spiral resting on one anothen'said.

, passageway having a constriction'preventing'movement of said spiral mass ther'ethroug'h, and means for withdrawing" .said filamentary material in uncoiled condition from said spiral -mass. through said constriction, said introducing means comprising means for bringing together said fila;

mentary material and said treating liquid to form a.

continuous streamand for introducing said stream from a point into said treating bath, and means for moving said point in a closed path about a substantially vertical axis to impart a spiral motion to said strearnv 7' 14. Process which comprises continuously passing a yarn of less than about 25,000 denier together with a liquid for treating the same and in contact therewith into a liquid treating bath and in the form of a series of crunodal loops of said yarn arranged in a spiral having a diameter greater than the diameter of said loops, sup

portingsaids'piral in said bath and above the bottom of said bath with successive convolutions of said spiral resting on one: another, and continuously withdrawing said filamentary material from the bottom of said spiral.

15 Process as set forth in claim 2 in which said filamentary material is'a yarn of, less than about 25,000 denier. I f

16. Apparatus as 'set forth in claim 7 in which said means for providing a bath of treating liquid comprises a stationary container for said bath. 

2. IN THE PROCESS FOR THE LIQUID TREATMENT OF FILAMENTARY MATERIAL, THE INDIVIDUAL FILAMENTS OF WHICH ALL EXTEND SUBSTANTIALLY IN THE DIRECTION OF THE LENGTH OF SAID FILAMENTARY MATERIAL, THE IMPROVEMENT WHICH COMPRISES INTRODUCING SAID FILAMENTARY MATERIAL INTO A LIQUID TREATING BATH CONTINUOUSLY IN THE FORM OF A SERIES OF CRUNODAL LOOPS OF SAID FILAMENTARY MATERIAL ARRANGED IN A SPIRAL HAVING A DIAMETER GREATER THAN THE DIAMETER OF SAID LOOPS, THE DENSITY OF SAID LIQUID BATH BEING LESS THAN THE DENSITY OF SAID FILAMENTARY MATERIAL WHEREBY SAID SPIRAL OF YARN LOOPS SINKS IN SAID BATH, SUPPORTING SAID SPIRAL IN SAID BATH WITH SUCCESSIVE CONVOLUTIONS OF SAID SPIRAL RESTING ON ONE ANOTHER, AND CONTINUOUSLY WITHDRAWING SAID FILAMENTARY MATERIAL FROM THE BOTTOM OF SAID SPIRAL.
 5. PROCESS FOR THE LIQUID TREATMENT OF FILAMENTARY MATERIAL THE INDIVIDUAL FILAMENTS OF WHICH ALL EXTEND SUBSTANTIALLY IN THE DIRECTION OF THE LENGTH OF SAID FILAMENTARY MATERIAL, WHICH COMPRISES CONTINUOUSLY FEEDING SAID FILAMENTARY MATERIAL, FEEDING A LIQUID FOR TREATING THE SAME INTO CONTACT WITH SAID FILAMENTARY MATERIAL TO FORM A 